Nation-building missions and armed democracy-promotion ventures are not essential to America’s security. We do not need, and should not want, any more Iraqs or Afghanistans. More than 5,000 dead Americans and nearly $2 trillion down the drain ought to deter Washington from pursuing similar schemes in the future.

It was bad enough during the Cold War when the United States appointed itself global policeman, but in recent years our nation has become the world’s armed social worker. U.S. leaders will find that to be an increasingly lonely role. Even America’s professed allies no longer have the military capabilities or the desire to join us as junior partners. Instead of berating them for a lack of loyalty, we ought to emulate their wisdom and restraint.